Hot disconnect replaceable water filter assembly

ABSTRACT

A filter assembly for filtering water from an external source, the filter assembly having a manifold assembly and a filter cartridge. The filter cartridge includes a cartridge engagement means while the manifold includes a manifold engagement means. The cartridge engagement means and manifold engagement means cooperatively interfacing for removable attachment of the filter cartridge to the manifold assembly. The cartridge engagement means and manifold engagement means oriented in a retaining relation during removal of the cartridge filter from the manifold assembly such that any entrained pressure within the cartridge filter is vented while the cartridge engagement means and manifold engagement means are in the retaining relation.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a Continuation of allowed U.S. patentapplication Ser. No. 11/013,269 entitled “HOT DISCONNECT REPLACEABLEWATER FILTER ASSEMBLY”, filed Dec. 14, 2004 now U.S. Pat. No. 7,481,398,which is a Continuation-In-Part application of U.S. patent applicationSer. No. 10/202,290, filed Jul. 24, 2002 now abandoned, which claims thebenefit of U.S. Provisional Application Nos. 60/308,757 filed Jul. 30,2001, and 60/559,593, filed Apr. 5, 2004. Each of the aforementionedapplications is incorporated herein by reference.

BACKGROUND OF THE DISCLOSURE

The present disclosure relates generally to the field of residential andcommercial filtration products, such as water filtration products. Thefilter assemblies can be used to filter any one of a range of fluids,such as water, oil, biological preparations, beer, wine, otherbeverages, other consumable liquids and the like. For convenience, thediscussion below focuses on water filtration, although the filterassemblies can generally be used for other applications based on thedisclosure herein.

Water filter assemblies, such as point-of-use water filtration systemshave become increasingly common in the residential and commercialenvironment. There are many advantages to these types of systems inaddition to the improvements to taste and appearance of the water. Insituations where the source water has been municipally treated,point-of-use systems allow the water to retain the disinfectingproperties imparted by the municipality until the moment of use suchthat chances of undesirable microbial contamination is correspondinglyreduced. These point-of-use filtration systems can also be individuallytailored to treat specific properties of the source water.

One disadvantage of point-of-use filtration systems in the residentialand commercial environment is that they must be designed to fit in thelimited spaces available to house the systems in these markets. As thedesign must be compact and unobtrusive, these systems must be designedto allow for frequent and easy replacement of used and exhausted filterelements. Because many of the users in the commercial and residentialmarket may be unfamiliar with the potential dangers of working with apressurized system, the filtration systems must also be designed withthe safety of the user in mind.

To that end, during normal operation of the filters utilized in thepoint-of-use water filtration systems, the potential for selfuncoupling, i.e., disconnection without user intervention, of the filtercartridge from the filter manifold should be eliminated to preventunwanted leakage and subsequent disengagement of the filter assemblywhile also permitting the assembly to disconnect safely should anincreased pressure condition occur beyond the structural failure pointof the filter assembly. Further, the act of uncoupling the filtercartridge utilized in the point-of-use water filtration systems from thefilter manifold utilized in the system should also permit the relief ofany excess pressure in a controlled manner to reduce the risk of damageor personal injury to the point-of-use water filtration system user.

SUMMARY OF THE DISCLOSURE

Water filter assemblies of the present disclosure meet theaforementioned requirements of the commercial and residential markets.Generally, a representative embodiment of a water filter assemblycomprises a cartridge assembly and a manifold assembly incorporating aninterconnection design for at least resisting and preferably preventingor rapid, violent, and unintentional separation of the cartridgeassembly from the manifold assembly as pressure in the water filtercomes to equilibrium with the ambient pressure. In general, improveddesigns for engaging a cartridge filter with a manifold involve ventingto the ambient atmosphere of the filter prior to the completedisengagement of the filter from the manifold. In some representativeembodiments described herein, filter assemblies comprise improvedengagement mechanisms for engaging a filter cartridge with a manifold inwhich representative embodiments of improved engagement mechanismscomprise helical threads and equivalents that perform an equivalenteffective engagement. In additional or alternative representativeembodiments, the engagement mechanism comprises a structure with twoengagement configurations, one being a fully engaged configuration inwhich the flow channels provide for flow from the manifold through thefilter and returning to the manifold and a second partly engagedconfiguration in which the filter cartridge is stably engaged with themanifold but the filter is vented to the ambient pressure.

One representative filter cartridge of the present disclosure comprisesa representative cartridge top member and representative cartridgefilter housing readily operatively connected to a representativemanifold assembly. The representative cartridge top member ispermanently attached to the representative cartridge filter housingthrough appropriate means such as, for example, spin or sonic welding orthe use of adhesives and other equivalent means that sufficientlyperform the required function thereof. In some presently preferredembodiments, in effecting such operative connection between therepresentative cartridge assembly and the representative manifoldassembly, at least one seal provides a watertight seal between therepresentative cartridge assembly and the representative manifold.Additionally, at least two seals operative arranged in a seriesrelationship provide for effecting a watertight seal between theunfiltered inlet water and the filtered outlet water to preventcontamination therebetween. In other representative embodiments, thewatertight seals can be positioned in other suitable configurations soas to isolate the unfiltered water flow and the filtered water flow fromeach other and from the ambient environment.

One aspect of some representative embodiments of the manifold assemblyand associated operatively connected cartridge top assembly comprisestructure such that, during replacement of cartridge assemblies on themanifold assembly, the pressurized water being supplied to the manifoldassembly is automatically and positively shutoff and any residualpressure within the filter assembly is sufficiently vented to allowbenign disengagement during disconnection of the cartridge assembly fromthe manifold assembly. Accordingly, one or more pressure relief portscan be spaced around the sidewall of the receiver well of the cartridgetop assembly to provide this venting after the supply water is shut offbut before the cartridge filter assembly is disengaged from the manifoldassembly, thus, resulting in increased safety to the user.

In another aspect, representative filter assemblies of the presentdisclosure have the ability to at least essentially, if not totally,eliminate any potential for representative cartridge filter assembliesto unexpectedly disconnect from the representative manifold assemblyduring normal operation under typical operating conditions. Therefore,in some representative embodiments, the present disclosure incorporatesrepresentative locking tabs on the representative cartridge top assemblyengaging mechanism that operatively interface with cooperativerepresentative depressions on the representative manifold assemblyengaging mechanism, providing a resistive force to this inherentdisconnecting phenomenon. Furthermore, the representative locking tabscan be configured to permit the representative filter assembly toselectively disconnect should an increase in the filter assemblyinternal pressure occur that could damage the assembly or nearbyobjects. The design of these locking tabs can be modified to respondselectively to various levels of increased internal pressure conditions,as described further below.

During installation or removal of a water filter, such as from apoint-of-use water filtration system, the user applies force such as,for example, rotatable or slidable force, to the filter housing. In somerepresentative embodiments, interconnection ramps located on the filterend cap are configured to interface with an internal ramp assembly ofthe water manifold such that the filter and manifold slidably engage ordisengage at the ramp assemblies. As the filter and manifold engage ordisengage, the molded engagement ramps on the filter end cap either comeinto contact or lose contact with a spring valve located in theunfiltered water flow channel of the manifold depending upon whether afilter is being installed or removed. The molded tabs operativelylocated on the manifold prevent disconnection and separation of thefilter from the manifold until essentially the entire length of thefilter end cap interconnection ramp has been traversed. Byappropriately, sufficiently sizing the length of the interconnectionramp in comparison to the engagement ramp, during disconnection, thewater filter assembly is allowed to vent and attain pressure equilibriumwith the external environment before the filter and manifold have beencompletely separated. In some representative embodiments, the engagementramp, being shorter than the interconnection ramp, results in a break inthe fluid circuit thereby resulting in the release of any pressureenergy stored in the filter through venting of the filter to the ambientatmosphere. Because pressure equilibrium is reached while the lockingtabs are still engaged, there is no longer energy available that couldlead to the rapid and violent separation of the components during thedisconnection process, thereby leading to increased safety for thesystem user.

In another representative aspect, the present disclosure describes arepresentative cartridge filter and a representative filter manifoldcomprising ramp-like interconnection members having multiple stages. Forexample, the interconnection members for both the cartridge filter andthe filter manifold can take the form of ramps having multiple angledportions and multiple substantially horizontal portions wherein theangled portions serve to transition the cartridge filter and the filtermanifold between different stages of connection while the horizontalportions serve to provide stable connection configurations, in which onestable configuration prevent physical detachment of the filter manifoldand cartridge filter while venting the cartridge filter to the ambientpressure. However, other representative embodiments with rotationalengagement or slidable engagement can provide desired venting with atwo-stage engagement.

In another representative aspect, the present disclosure describes arepresentative filter assembly for filtering water from an externalsource, the filter assembly including a representative manifold assemblymountable to a representative appliance and being in fluid communicationwith the external water source and a representative cartridge assembly,the cartridge assembly being replaceable fluidly connectable to themanifold assembly by means of a hot disconnect that prevents rapid,unintentional and violent disengagement of the cartridge assembly fromthe manifold assembly. The manifold assembly is operably fluidlyconnectable at an inlet to a water source to be filtered and has afiltered water outlet and operative connecting members for removablyconnecting to the cartridge top member and has a mounting means attachedto the manifold providing rotational travel to the cartridge top memberfor installation, removal and replacement of the cartridge filter.

According to present disclosure, representative adapters can be used tointroduce desired attachment functions to an existing representativemanifold. With the use of an adapter, the existing manifold is connectedto an effective manifold for operatively coupling to a filter cartridge.Thus, a desired representative filter cartridge can be attached to theresulting effective manifold at the adapter such that the operativelyconnected filter cartridge and effective manifold, formed from theadapter connected to the existing manifold, can have various desiredengagement and disengagement functionalities, such as venting and/or atwo-stage engagement mechanism. In some representative embodiments, arepresentative cartridge top member operatively connects with therepresentative filter cartridge and has a fluid inlet, the inlet beingfluidly communicable with the filter cartridge and being in fluidcommunication with an adapter assembly valve and further having asealing means, the sealing means isolating an inlet flow of unfilteredwater to the filter cartridge from a non-wetted portion of the manifoldassembly and having a cartridge coupler fluid outlet, the outlet beingfluidly communicable with a filter cartridge outlet and being in fluidcommunication with the manifold coupler outlet and further havingsealing means, the sealing means isolating an inlet flow of unfilteredwater to the filter cartridge from an outlet flow of filtered water fromthe filter cartridge.

In another representative aspect, the present disclosure is directed toa cartridge assembly and additionally a method of disengaging thecartridge assembly from a manifold assembly.

In yet another representative aspect, the present disclosure is directedto a filtration assembly comprising a cartridge filter and a manifoldassembly. Both the cartridge filter and the manifold assembly cancomprise engagement members defined by alternating horizontal and angleportions wherein the angled portions promoted attaching and withdrawingthe cartridge filter from the manifold assembly and wherein thehorizontal portions retainingly interface to prevent prematuredisconnecting of the cartridge filter from the manifold assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of the manifold assembly member of thepresent disclosure taken through the inlet and outlet ports.

FIG. 2 is a sectional view of the manifold assembly member of thepresent disclosure taken perpendicular to FIG. 1.

FIG. 3 is an exploded perspective view of the manifold assembly.

FIG. 4 is an underside perspective view of the manifold assembly.

FIG. 5 is a plan view of the cartridge top member.

FIG. 6 is a perspective view of the cartridge top member, topside.

FIG. 7 is a perspective view of the cartridge top member, underside.

FIG. 8 is a cross sectional view of the cartridge top member takenthrough its center.

FIG. 9 is an exploded perspective view of the cartridge assembly.

FIG. 10 is a side elevational sectional view of the cartridge assembly.

FIG. 11 is a perspective view of the cartridge filter glue dam; and

FIG. 12 is a plan view of the cartridge filter glue dam.

FIG. 13 is a perspective, cap-side view of an embodiment of a cartridgefilter having a multiple stage attachment mechanism.

FIG. 14 is a perspective, base-side view of the cartridge filter of FIG.13.

FIG. 15 is an exploded, perspective view of the cartridge filter of FIG.13.

FIG. 16 is a side view of the cartridge filter of FIG. 13.

FIG. 17 is an alternative side view of the cartridge filter of FIG. 13.

FIG. 18 is a cap-side end view of the cartridge filter of FIG. 13.

FIG. 19 is a base-side end view of the cartridge filter of FIG. 13.

FIG. 20 is a fragmentary perspective view of the cartridge filter ofFIG. 13 with an expanded view of a filter cap.

FIG. 21 is a cap-side perspective view of the filter cap of FIG. 20.

FIG. 22 is a fragmentary side view of the cartridge filter of FIG. 13with an expanded view of the filter cap of FIG. 20.

FIG. 23 is a section view of the cartridge filter of FIG. 13 in whichthe section is taken through the center of the cartridge.

FIG. 24 is an exploded, perspective view of a distribution manifold.

FIG. 25 is a filter-connection end view of the distribution manifold ofFIG. 24.

FIG. 26 is an inflow-outflow-connection end view of the distributionmanifold of FIG. 24.

FIG. 27 is a side view of the distribution manifold of FIG. 24 withhidden structure shown in phantom lines.

FIG. 28 is a sectional side view of the distribution manifold of FIG. 24taken along line 28-28 of FIG. 27.

FIG. 29 is a side view of the distribution manifold of FIG. 24.

FIG. 30 is a section view of the distribution manifold of FIG. 24 takenat line 30-30 of FIG. 29.

FIG. 31 is an exploded, perspective view of a water filtration systemcomprising the cartridge filter of FIG. 13 and the distribution manifoldof FIG. 24.

FIG. 32 is an alternative exploded, perspective view of the waterfiltration system of FIG. 31 with the manifold and cartridge filteraligned for attachment.

FIG. 33 is a fragmentary, cut-away side view of the water filtrationsystem of FIG. 31 with a portion of the wall of the manifold cut away toshow a portion of the multistage ramp engagement mechanism.

FIG. 34 is a side view of a multiple-stage ramp engagement mechanism ina disconnected orientation.

FIG. 35 is a side view of the multiple-stage ramp engagement mechanismof FIG. 34 in a first partially-engaged orientation.

FIG. 36 is a side view of the multiple-stage ramp engagement mechanismof FIG. 34 in a second partially-engaged orientation.

FIG. 37 is a side view of the multiple-stage ramp engagement mechanismof FIG. 34 in a third partially-engaged orientation.

FIG. 38 is a side view of the multiple-stage ramp engagement mechanismof FIG. 34 in a fully engaged orientation.

FIG. 39 is a side, perspective view of an adapter for adapting themanifold assembly of FIG. 1 to accept the cartridge filter of FIG. 13.

FIG. 40 is an exploded, perspective view of a distribution manifold anda cartridge filter having a linear multi-stage interconnectionmechanism.

DETAILED DESCRIPTION OF THE DRAWINGS

A representative filter assembly or point-of-use water filtration systemof the present disclosure is shown generally at 10 in the figures. Thefilter assembly 10 has two major components: a manifold assembly 12 anda cartridge assembly 14. The cartridge assembly 14 further comprisesthree subcomponents: cartridge top member 16, cartridge housing 18, andfilter element 19.

As illustrated in FIGS. 1, 2, 3, and 4, the manifold assembly 12,presently preferably, includes a general manifold body 20. Inletcartridge fitting 23 is, presently preferably, press-fit into inlet bore21 of manifold assembly body 20, forming inlet port 22. A gap 27,illustrated in FIG. 1, is, presently preferably, formed between inletbore 21 and inlet cartridge fitting 23. Inlet port 22 is sealed from gap27, presently preferably, by means of O-ring 30 or the like. Inlet port22 narrows into tubular inlet flow passage 29. Inlet flow passage 29leads to valve well 42. Valve well 42 is, presently preferably,positioned to accept, presently preferably, both high-flow valve 28 andbiasing spring 26. Valve well 42 is fluidly operatively connected toinlet bore 52 of cartridge insert 50 (see FIG. 3). High-flow valve 28 isseated in and also longitudinally translates within valve well 42. Inletbore 52 has an annular surface 37 upon which ridge 33 of high-flow valve28 sits to create a water-tight seal when biasing spring 26 isdecompressed.

From FIG. 3, cartridge insert 50 has two main sections, an expandedupper body portion 54 and a second reduced body portion 56. Body portion56 has a significantly reduced diameter when compared to the diameter ofupper body portion 54. Cartridge insert 50 is, presently preferably,fixedly operatively connected to base assembly 43 of manifold assembly12 at sealing surface 47, as shown in FIG. 4. Cartridge insert 50 andbase assembly 43 are, presently preferably, sealed therein by gasket 48or the like, which separates pressurized inlet and outlet water from thecavity of manifold assembly body 20. The base assembly 43 is operativelyconnected with cartridge insert 50 and, presently preferably, fluidlyoperatively connects outlet 44 of manifold assembly 20 with inlet bore52 of cartridge insert 50, as well as inlet 46 of manifold assembly 20with outlet bore 40 of cartridge insert 50.

Expanded upper body portion 54 includes groove 38. Groove 38 comprises aseal 34, presently preferably an O-ring, for sealing pressurized waterfrom within receiver well 106 of cartridge top member 16 (shown in FIG.6 and described below) from the cavity of general manifold body 20.Reduced body portion 56 further includes a pair of grooves 36. Thesegrooves 36 are situated in series and hold seals 32, preferably beingO-rings, to separate unfiltered inlet water within receiver well 106from filtered outlet water. Reduced body portion 56 also has boredthrough its longitudinal center outlet bore 40 for conveying filteredoutlet water from cartridge assembly 14.

Turning now to FIG. 3, outlet bore 40 continues through expanded upperbody portion 54 by, presently preferably, means of a conical projection59 within which filtered outlet water flows. Conical projection 59 has,presently preferably, a wider diameter at its base than its peak, thebase therefore, presently preferably, narrowing to its point of fluidcoupling with outlet flow passage 31. Outlet bore 40, presentlypreferably, retains a constant inside diameter flow path. From FIG. 1,flow passage 31 has an approximate 90.degree. turn leading to outletflow passage 35. As before, outlet port 24 is, presently preferably,formed from the press-fitting of outlet cartridge fitting 25 into outletbore 39 of manifold assembly body 20. A similar sealing means of anO-ring 30 is, presently preferably, employed to seal the subsequent gap27 formed between outlet cartridge fitting 25 and outlet bore 39.

Manifold assembly 12 further has a top manifold hood 62 attached tomanifold assembly body 20 using manifold hood connectors 60 as shown inFIG. 3.

Referring to FIG. 4, the underside of manifold assembly body 20,presently preferably, has protruding therefrom cartridge receiver 72 foroperatively connecting with cartridge top member 16. The operativelyconnecting mechanism between cartridge receiver 72 and cartridge topmember 16 is, presently preferably, through interior helical tabs 70located on the inside margin 73 of cartridge receiver 72. Tabs 70 are,presently preferably, diametrically opposed on inside margin 73. Thesetabs 70, presently preferably, extend flush from the bottom surface ofreceiver 72 and, presently preferably, spiral upward at an approximate8.degree. angle along margin 73 to a position, presently preferably,less than half the circumference away from their point of origin. Thetop surface 74 of these tabs 70, presently preferably, provides thesupporting structure for and, presently preferably, operatively connectswith external helical tabs 104 of cartridge top member 16, shown in FIG.6 and described below.

Turning now to FIGS. 6 and 7, cartridge top member 16, presentlypreferably, includes member body 100. Member body 100, presentlypreferably, has a margin 101 from which exterior helical tabs 104operatively connect with interior helical tabs 70 of cartridge receiver72. As with interior helical tabs 70, exterior helical tabs 104,presently preferably, spiral upward, presently preferably, at anapproximate 8.degree. angle along margin 101 to a, presently preferred,position less than half the circumference away from their point oforigin. The underside surface 128 of these tabs is, presentlypreferably, supported by top surface 74 of interior helical tabs 70 ofmanifold assembly 12, shown in FIG. 4. As can be seen in FIGS. 6 and 7,exterior helical tabs 104, presently preferably, have at their endpoints ramps 120 for facilitating engagement with interior helical tabs70.

Cartridge top member body 100 has, presently preferably, defined thereininterior receiver well 106 with inside margin 112 for sealing withO-ring 34 of manifold assembly 12 as shown in FIG. 1. This effects afluid seal between unfiltered inlet water within receiver well 106 andthe cavity of manifold assembly body 20.

As illustrated FIGS. 5, 6, 7, and 8, a plurality of inlet orifices 114are, presently preferably, formed within the bottom surface of receiverwell 106. These orifices 114 are, presently preferably, spacedcircumferentially and equidistant from each other, although otherspacing and numbers of orifices can be used, as would be understood byone skilled in the art. A distinct feature of these orifices 114 is thatthe inside diameter of any individual orifice is designed such that theadhesive forces between the inside surface and any remaining waterwithin that orifice, presently preferably, allow for capillary action toprevent dripping when the cartridge assembly 14 is disengaged from themanifold assembly 12. These orifices 114, presently preferably, directinlet water to cartridge housing 18.

Outlet bore 122 is, presently preferably, bored through the center ofcartridge top member 16. Within outlet bore 122 reduced body portion 56of cartridge insert 50 is, presently preferably, engaged for conveyanceof filtered water. A lip 124, presently preferably, protrudes from theunderside of outlet bore 122, providing proper positioning of filter 19within cartridge assembly 14. Dual ramps 102, presently preferably,extend upward from the bottom of receiver well 106. One or the other ofthe ramps 102, presently preferably, radially aligns with high-flowvalve 28 contact surface 41 to compress and open the valve 28 whencartridge top member 16 is, presently preferably, rotatably moved intoplace to operatively connect with manifold assembly 12.

The underside surface 128 of each helical tab 104, presently preferably,has a locking tab 108 for, presently preferably, operatively connectingwith a cooperative depression 109 located in interior helical tab 70 ofmanifold assembly 12. As will be seen, these locking tabs 108, presentlypreferably, interface with depressions 109 during engagement ofcartridge assembly 14 with manifold assembly 12 to lock the cartridgeassembly 14 in place and to provide a degree of burst protection to thecomponents of filter assembly 10, i.e. to resist unexpecteddisconnection of the cartridge assembly 14 from the manifold assembly12. The locking tabs 108 will, presently preferably, disengage from therespective depressions 109, presently preferably, permitting thecartridge assembly 14 to back off from manifold assembly 12 at apredefined level of hydraulic pressure for the benign disengagementthereof.

Without locking tabs 108, normal pressure levels of the incoming waterservice and associated vibrations would slowly cause the cartridgeassembly 14 to disconnect from manifold assembly 12, resulting inleakage and the eventual total disengagement of the cartridge assembly14 from the manifold assembly 12. One unique feature, among others, oflocking tabs 108 in the representative embodiment of the Figures, isthat they can be designed such that they do not allow for this gradualdisconnecting of the filter assembly under normal line pressureconditions and within normal line pressure tolerances, but will commencedisconnecting at a certain pressure condition below the structuralstrength limits of the filter assembly. Generally, normal line pressureconditions range from about 20 psig to about 120 psig. In thisrepresentative embodiment and in other representative embodiments suchas those described below, the filters can be designed to disconnect atpressures above about 120 psig, and in other presently preferredembodiments at pressures above a value from about 150 psig to about 180psig. A person of ordinary skill in the art will recognize thatadditional ranges of pressure values within these explicit pressureranges are contemplated and are within the present disclosure. Thedesign of the locking tabs 108, presently preferably, determines thispressure condition by being a more aggressive design, such as withdeeper depressions 109, or a less aggressive design, such as withshallower depressions 109, a more aggressive design seating more firmlyin the depression 109 and requiring greater pressure relative to lessaggressive designs to unseat the locking tabs 108 from the depressions109.

Referring to FIGS. 4 and 6, manifold assembly 12 and cartridge topmember 16, presently preferably, have alignment markers, 200 and 202respectively, to indicate alignment of both components and engagement oflocking tabs 108.

As illustrated in FIG. 7, the cartridge top member 16, presentlypreferably, has a margin 116 extending circumferentially from body 100.The interior face 117 of surface 116, presently preferably,progressively slopes centerward to inlet orifices 114. This slope allowsfor a smoother transition and flow pattern from the interior spacewithin surface 116. Also on the interior face 117 are, presentlypreferably, two weld facilitators 118. The weld facilitators 118 are,presently preferably, diametrically opposed from each other.

As illustrated in FIGS. 6 and 8, defined around the perimeter of uppersealing surface 112 of receiver well 106 are, presently preferably, aplurality of vent ports 110. Vent ports 110 are, presently preferably,spaced equidistant around the diameter of sealing surface 112. Thesevent ports 110, presently preferably, separate the surface 112 from theinterior cavity of manifold assembly body 20, as shown in FIG. 1. Aswill be seen, these vent ports 110, presently preferably, allow forrelief of pressure trapped in the cartridge assembly 14 before completedisengagement during the disassembly of cartridge assembly 14 frommanifold assembly 12. The top edge 126 of receiver well 106 is,presently preferably, chamfered to facilitate this relief of pressure.

Turning now to the representative cartridge housing assembly 18 as shownin FIGS. 9 and 10, cartridge housing assembly 18, presently preferably,comprises cartridge housing body 150 and its components as well asfilter assembly 19. Cartridge housing body 150 is, presently preferably,a cylindrical housing tapered at one end for insertion of filterassembly 19. Lateral supports 154, presently preferably, protrude inwardfrom the narrow end and herein defined as bottom of body 150 forlongitudinally supporting filter assembly 19 in place. Concentric andcenter to supports 154 is, presently preferably, an upward directedalignment projectile 156, also used to support and center filterassembly 19 within cartridge housing body 150. Handle 158 is, presentlypreferably, formed from the bottom of housing body 150 and is utilized,presently preferably, to assist in applying rotational force tocartridge assembly 14.

Filter 19 comprises, presently preferably, carbon filter 180 or othertype filter. The carbon filter 180 is, presently preferably, made ofactivated carbon with roughly about one micron particle size in abinder. The carbon block forming the carbon filter 180 has, presentlypreferably, an inner margin 191 that defines an axial bore 190. Thepresently preferred representative embodiment of carbon filter 180 is amolded design as shown in FIG. 10 in which axial bore 190 does not,presently preferably, extend all the way through filter 180, but insteadto a point in which a portion of filter medium, presently preferably,exists between the end of axial bore 190 and alignment projectile 156.With this design, the full exterior surface of filter 180 in fluidcontact with the inlet water, presently preferably, serves as a filtermedium.

Another representative alternative embodiment, presently preferably,comprises an extruded design in which axial bore 190 does extend all theway through carbon filter 180. The extruded design, presentlypreferably, necessitates an end dam on the bottom of carbon filter 180to prevent unfiltered water migration into axial bore 190. The extrudedembodiment is defined by dashed lines 199 extending through carbonfilter 180, as shown in FIG. 10.

The outlet of filter element 19, presently preferably, comprisesadhesive 182 and glue dam 184. As shown in FIGS. 11 and 12, glue dam 184further consists of disc 185, supports 186, and outlet tube 188. Disc185, presently preferably, has a diameter that is less than that of theinside surface of cartridge housing body 150, resulting in a flow pathfor unfiltered water to filter 180, shown as annular space 152 in FIG.10. To facilitate the flow of water, the outer edge of disc 185 anglesdownward via outer edge 187.

Disc 185 further includes spacers 189, presently preferably, placedequidistant around outer edge 187, further defining the annular spaceavailable as a path for unfiltered water. Angled supports 186 are,presently preferably, spaced equidistant around the top face of glue dam184 to brace outlet tube 188. The interior surface of outlet tube 188 isdefined herein as sealing surface 192. Sealing surface 192 is sized toaccept, presently preferably, O-rings 32 or the like as described abovein FIG. 3 for the purpose of separating unfiltered inlet water fromfiltered outlet water. The bottom of sealing surface 192 is defined asoutlet face 195. Within outlet face 195 is a bore defining outletorifice 194, for operatively fluidly connecting filtered outlet water offilter bore 190 to outlet bore 40 of cartridge insert 50.

As shown in FIG. 9, cartridge top member 16 operatively connects withcartridge housing assembly 18 through the coupling of margin 116 withthe inside surface 196 of cartridge housing 150.

In operation, from an external connection (not shown) unfiltered waterflows through inlet port 22 of FIG. 1 to inlet flow passage 29 and intovalve well 42. When manifold assembly 12 is not engaged with cartridgeassembly 14, biasing spring 26 imparts a force upon high-flow valve 28,depressing it from valve well 42 into inlet bore 52 of cartridge insert50. This effects a watertight seal at annular surface 37 between valvewell 42 and inlet bore 52 of cartridge insert 50.

In coupling operation, manifold assembly 12 is engaged with cartridgeassembly 14 and specifically, cartridge top member 16 as follows:Manifold assembly 12 is engaged with cartridge assembly 14 by matchingup external helical tabs 104 of cartridge top member 16 with internalhelical tabs 70 of manifold assembly 12, using a ramp 120 as an initialguide. The operatively connecting helical tabs 70, 104 will begin toengage the manifold assembly 12 with the cartridge assembly 14 when arotational motion is imparted to the cartridge assembly 14 relative tomanifold assembly 12. This rotational motion will translate into alongitudinal displacement of cartridge assembly 14 into manifoldassembly 12, sealing both interior sealing surface 192 of outlet tube188 on FIG. 8, as well as sealing surface 112 of cartridge top member16.

When alignment marker 200 of manifold assembly 12 (see FIG. 4) is linedup with alignment marker 202 of cartridge top member 16 (see FIG. 6),then ramp 102 of cartridge top member 16 will have fully depressedhigh-flow valve 28 within valve well 42 of manifold assembly 12 againstthe compressive force of biasing spring 26. This allows inlet water toflow through as described above. The alignment of markers 200 and 202also indicates that locking tabs 108 have engaged the depressions 109.

During normal engagement, as described below, the axial force impartedon high-flow valve 28 by ramps 102 of cartridge top member 16 translatesthrough the body of valve 28, compressing biasing spring 26 and allowinginlet water to flow from inlet flow passage 29 through to receiver well106 of cartridge top member 16.

Within receiver well 106, pressurized water is forced through inletbores 114 (see FIG. 6) along interior surface 117 of FIG. 7 and guidedaround to the outer circumference of disc 185 and down outer edge 187 ofFIG. 9. Flow proceeds into the annular space 152 defined between theexterior of filter 180 and the interior surface of cartridge housing 150as shown in FIG. 10. Differential pressure between the exterior offilter 180 and axial bore 190 forces this inlet water from annular space152 through the filter to axial bore 190. From bore 190, filtered waternow flows through the flow restriction outlet orifice 194 through outletbore 40 of cartridge insert 50 to outlet flow passage 31 of manifoldassembly 12. From there, filtered water exits manifold assembly 12through outlet flow passage 35 and out outlet port 24 to an externalmeans connected thereto (not shown).

In an alternative embodiment, an adapter could be used to facilitateinterconnection of the cartridge assembly 14 and the manifold assembly12. Such an adapter would allow for the use of filter assemblycomponents 10 not originally designed for use with one another.

The disengagement of manifold assembly 12 from cartridge assembly 14proceeds as follows, under the definition that alignment marker 200 ofmanifold assembly 12 is lined up with alignment marker 202 of cartridgetop member 16, at 0.degree. It should be noted that all relativerotational motion between manifold assembly 12 and cartridge assembly 14also provides relative motion along the longitudinal axis. As rotationalforce is applied to cartridge assembly 14 to disengage it from manifoldassembly 12, from 0.degree. to substantially 17.degree. from alignment,locking tabs 108 are unseated from depressions 109. Simultaneously, thecompressive force of biasing spring 26 acts to close the high-flow valve28 as the valve 28 rides down the ramp 102 (see FIG. 6). As valve 28descends (longitudinal relative motion), ridge 33 approaches annularsealing surface 37. At substantially 17.degree. of rotation, biasingspring 26 has fully pressed ridge 33 of high-flow valve 28 into contactwith annular sealing surface 37, thereby stopping the flow of inletwater to the cartridge assembly. As rotation proceeds, at substantially34.degree. from alignment, sealing surface 112 will, presentlypreferably, begin to disengage longitudinally from O-ring 34, thusopening vent ports 110 to ambient and allowing vent ports 110 to relieveany excess pressure within cartridge assembly 14. As separation ofcartridge assembly 14 from manifold assembly 20 advances, presentlypreferably, at approximately 120.degree. from alignment, cartridgeassembly 14 will be free to fully disengage from manifold assembly 12.

Under normal conditions of system pressure and vibration, the existenceof locking tabs 108 and depressions 109 will, presently preferably,necessitate the manual disengagement of manifold assembly 12 fromcartridge assembly 14 as described above. However, upon an overpressurecondition within the filter assembly, as defined by the level ofaggressive design utilized in tabs 108 and depressions 109, internalpressure will, presently preferably, unseat locking tabs 108 fromdepressions 109 without the aid of external means, thereupon commencingthe benign disengagement sequence as described above.

Referring to FIGS. 13-23, a representative embodiment of a filtercartridge 300 comprising a filter cap 302, a filter media 303 and afilter body 304 is illustrated in which the filter cartridge can be usedto complete a two stage engagement structure. Filter media 303 cancomprise a wide variety of filtering medias for example depth filtrationmedia, surface filtration media, sand filtration media, activated carbonfiltration media, ion exchange filtration media, cross-flow membranefiltration media and hollow fiber filtration media. Filter cap 302 andfilter body 304 can be fabricated of suitable polymeric materials suchas polypropylene, polycarbonate or polyethylene. Alternatively, filtercartridge 300 can be fabricated from modified polyolefins such as, forexample, metallocene modified polypropylene or polyethylene polymers andcopolymers as well as either high or low density polyethylene polymers,having advantageous properties such as increased strength, elasticity orincreased ultimate elongation percentages such as disclosed in U.S.patent application Ser. No. 10/377,022, which is herein incorporated byreference to the extent not inconsistent with the present disclosure. Insome embodiments, filter cap 302 may be constructed of a first polymer,such as polypropylene, having a specific quality such as, for example,strength or rigidity while filter body 304 is constructed of a secondpolymer having a different design quality such as, for example,increased ultimate elongation percentage or increased stretch, withsuitable polymers being metallocene modified polypropylene orpolyethylene polymers and copolymers as well as either high or lowdensity polyethylene polymers. Filter cap 302 and filter body 304 areoperatively joined using any suitable joining technique such as, forexample, an engageable thread 305 as illustrated in FIG. 15 or otheralternative joining techniques such as adhesives, heat welding, spinwelding, ultrasonic welding and the Like. Filter cartridge 300 generallycomprises an attachment end 306 and a handling end 308.

Filter cap 302 can comprise a pair of opposed and identically configuredmulti-stage filter attachment members 310 a, 310 b, for exampleattachment ramps as illustrated in FIGS. 13-23. As clearly illustratedin FIGS. 17, 20 and 21, multi-stage filter attachment member 310 a cancomprise a first angled portion 312 a, a first horizontal portion 314 a,a second angled portion 316 a, a second horizontal portion 318 a and athird angled portion 319 a while correspondingly, multi-stage filterattachment member 310 b can comprise a first angled portion 312 b, afirst horizontal portion 314 b, a second angled portion 316 b, a secondhorizontal portion 318 b and a third angled portion 319 b.

As clearly illustrated in FIGS. 18, 20, 21 and 23, filter cap 302comprises a projecting insertion wall 320. A plurality of ventingnotches 322 is spaced about the inner rim of the insertion wall 320,although a single vent or a different number of venting notches can beused relative to the venting notches shown in the Figures. Filter cap302 further comprises an interface surface 324 having a plurality offeed throughbores 326 and a return throughbore 328. As illustrated,interface surface 324 can further comprise a pair of arcuate kick-offramps 330 a, 330 b.

Referring now to FIGS. 24-30, an embodiment of a distribution manifold332 configured for operable interfacing with filter cartridge 300 isillustrated. Distribution manifold 332 generally comprises a filter end334 and a distribution end 336, although alternative embodiments canhave distribution connections along a side and/or in the same generaldirection as the filter end. In one representative embodiment,distribution manifold 332 is constructed of the same polymeric materialas cartridge filter 300. Alternatively, distribution manifold 332 cancomprise an alternative material selected for qualities such asstrength, rigidity, cost and/or ease of fabrication. As illustrated inFIGS. 26, 29 and 30, distribution end 336, presently preferably,comprises a pair of tube connectors 338 a, 338 b for interconnection toa feed water tube 340 and a filtered water tube 342. As illustrated inFIGS. 25, 29 and 30, filter end 334, presently preferably, comprises anexterior wall 344, an engagement surface 346 and an engagement body 348.Engagement surface 346 can comprise a feed throughbore 347 a, configuredto operatively accept a feed valve assembly 349, and a returnthroughbore 347 b. Feed valve assembly 349 can comprise a valve body 349a and a spring 349 b. Engagement body 348 can comprise a projectingmember 350, a projecting feed throughbore 351 a, a projecting returnthroughbore 351 b, a pair of projection grooves 352 a, 352 b, a pair ofprojection seals 353 a, 353 b, a circumferential groove 354 and acircumferential seal 355. Engagement body 348, presently preferably, isoperatively connected to engagement surface 346 such that a feed fluidcircuit 357 a is defined by the projecting feed throughbore 351 a, thefeed throughbore 347 a, the tube connector 338 a and feed water tube 340while a filtered fluid circuit 357 b is defined by the projecting returnthroughbore 351 b, the return throughbore 347 b, the tube connector 338b and filtered water tube 342. Return throughbore 351 b is, presentlypreferably, fluidly interconnected with the filtered water tube 342while the feed throughbore 347 is fluidly interconnected with the feedwater tube 340.

As illustrated in FIGS. 25, 28 and 33, filter end 334, presentlypreferably, comprises a pair of multi-stage manifold attachment members356 a, 356 b, illustrated as attachment ramps, on an interior perimeterwall 359 of the distribution manifold 332. Manifold attachment members356 a, 356 b are configured correspondingly to multi-stage filterattachment members 310 a, 310 b such that manifold attachment member 356a, presently preferably, comprises a first angled portion 358 a, a firsthorizontal portion 360 a, a second angled portion 362 a, secondhorizontal portion 364 a and third angled portion 365 a while manifoldattachment member 356 b similarly comprises a first angled portion 358b, a first horizontal portion 360 b, a second angled portion 362 b,second horizontal portion 364 b and third angled portion 365 b.

In order to provide filtered water, filter cartridge 300 is operativelyconnected to distribution manifold 332 to form a filtration system 366,as illustrated in a disconnected configuration in FIGS. 31, 32 and 33.First, attachment end 306 is oriented to face filter end 334, as shownin FIGS. 32 and 33. Filter cartridge 300 is directed toward distributionmanifold 332 such that the insertion wall 320 enters the interior spacedefined by exterior wall 344. At the same time, projecting member 350 isaligned with return throughbore 328. At this point, filter attachmentmembers 310 a, 310 b are in proximity to manifold attachment members 356a, 356 b, for example as illustrated in FIG. 34. While engagement of thefilter attachment members 310 a, 310 b and manifold attachment members356 a, 356 b is only and illustrated with respect to filter attachmentmember 310 a and manifold attachment member 356 a, it will be understoodby one of ordinary skill in the art that filter attachment member 310 band manifold attachment member 356 b, presently preferably,simultaneously engage in a like manner. Furthermore, it will beunderstood that in some embodiments both filter attachment members 310a, 310 b and manifold attachment members 356 a, 356 b are, presentlypreferably, configured in an opposed relation such that filterattachment member 310 a engages similarly with both manifold attachmentmembers 356 a, 356 b while filter attachment member 310 b, presentlypreferably, is also engageable with both manifold attachment members 356a, 356 b. In some alternative embodiments, there can be instances inwhich, only one operable orientation is desired for filter cartridge 300to operatively connect to distribution manifold 332 to form filtrationsystem 366. One representative example can comprise filtration system366 utilizing crossflow filtration media with filter cartridge 300, suchas, for example, membrane or hollow-fiber based crossflow filtrationsystems as disclosed in U.S. patent application Ser. No. 10/838,140,which is herein incorporated by reference to the extent not inconsistentwith the present disclosure. With respect to crossflow filtrationsystems, the addition of an additional concentrate fluid circuit in thecartridge filter and/or manifold can necessitate that filter attachmentmembers 310 a, 310 b and manifold attachment members 356 a, 356 b engagein a single, specified orientation so as to properly define and completethe additional fluid circuit associated with crossflow filtrationsystems.

As illustrated in FIG. 34, filter attachment member 310 a and manifoldattachment member 356 a can be positioned such that first angled portion312 a is in proximity to first angled portion 358 a. The installerrotatably directs handling end 308, presently preferably, such that thefilter cartridge 300 is rotatably inserted with respect to thedistribution manifold 332. As the first angled portion 312 a and firstangled portion 358 a, presently preferably, engage each other, thefilter cartridge 300 and distribution manifold 332 are drawn closertogether. As the filter cartridge 300 is rotated further, firsthorizontal portion 314 a and first horizontal portion 360 a are,presently preferably, directed into intimate contact as shown in FIG.35. This corresponds with the first engagement stage (partially engagedconfiguration) and is a stable engagement position.

As the filter cartridge 300 is rotated further, first angled portion 312a interfaces with second angled portion 362 a while the second angledportion 316 a engages the first angled portion 358 a in a transitionbetween the partially engaged configuration and the fully engagedconfiguration as shown in FIG. 36, thus, further drawing together filtercartridge 300 and distribution manifold 332 such that projection seals353 a, 353 b sealingly engage the wall surrounding return throughbore328 while circumferential seal 355 sealingly engages the interiorperimeter surface of the projecting insertion wall 320. Continuedrotation of the filter cartridge 300 causes first horizontal portion 314a to, presently preferably, slidingly contact second horizontal portion364 a while the second horizontal portion 318 a engages the firsthorizontal portion 360 a, as shown in FIG. 37. This is the secondengagement stage. It will be understood by a person of skill in the artthat horizontal portions are substantially horizontal in that theyprovide resistance against rotation in response to standard operatingpressures exerted on the filter cartridge. Attachment of the filtercartridge 300 to the distribution manifold 312 is complete and is in afully engaged configuration when first angle portion 312 a seats againstthe third angled portion 365 a while the third angle portion 319 aengages the first angle portion 358 a, as illustrated in FIG. 38. As thefilter cartridge 300 and distribution manifold 312 approach an installedposition, one of the arcuate kick-off ramps 330 a, 330 b engages thefeed valve assembly 349 such that spring 349 b is compressed and feedfluid circuit 357 a is opened to incoming water. As the rotation ofcartridge filter 300 is completed, cartridge filter 300 and distributionmanifold 332, presently preferably, cannot disengage without rotatingthe cartridge filter 300 in a direction opposed to that indicated inFIGS. 40-44.

In operation, feed water flows through the feed flow circuit 357 a intothe filter cartridge 300. The feed water is directed through the filtermedia 303 such that selected contaminants such as, for example, ionic,organic or particulate, are removed from the water such that filteredwater is present in the center of the filter media 303. Purified waterflows out of the filter cartridge 300 by way of the return throughbore328 and filtered fluid circuit 357 b.

During operation of the filtration system 366, pressure such as, forexample, water or gas pressure, can become entrained with the filtercartridge 300. If gases are entrained within the filter cartridge 300during operation, the gases will become compressed by pressure withinthe system. Depending upon the mounting orientation of the filtercartridge 300, compressed gases can provide for violent disengagement ofthe filter cartridge 300 from the distribution manifold 332. For exampleif a filter cartridge 300 is, presently preferably, mounted such thatthe filter cartridge 300 is above the distribution manifold 332, anycompressed gases will be found at the top end of the filter cartridge300. When the filter cartridge 300 is removed from the distributionmanifold 332, compressed gases may drive a pressurized fluid out thebottom of the cartridge filter 300 whereby the cartridge filter 300 isessentially launched from the distribution manifold 332 as gases expandupon release of pressure upon disengagement.

In a filtration assembly with a single stage disengagement mechanism,stored energy within a cartridge filter can cause the violentdisengagement of the cartridge filter from a distribution manifold. Asdescribed in the present disclosure, any stored energy, stored in theform of a compressed gas or pressurized fluid, is vented prior to thefilter cartridge 300 and distribution manifold 332 becoming disengaged.For example, to remove the filter cartridge 300, a user would, presentlypreferably, direct the handling end 308 in a direction opposed to theinstallation direction. As the first angle portion 312 a slides down thethird angle portion 365 a, projecting member 350, presently preferably,begins to withdraw from the return throughbore 328 and one of thearcuate kick-off ramps 330 a, 330 b disengages from the feed valveassembly 349 such that spring 349 b is released and feed fluid circuit357 a is closed to incoming water. This, presently preferably, preventsany pressure energy from being imparted to the filter cartridge 300.Further rotation of the cartridge filter causes first angle portion 312a to slide down second angle portion 362 a causing projecting member 350to withdraw farther from the return throughbore 328. This, presentlypreferably, causes the seal created by projection seals 353 a, 353 b tobe broken when any entrained energy in the filter cartridge 300 isdispelled. The energy, present as fluid or gas pressure, is then ventedout venting notches 322. While the pressure is vented, first horizontalportion 314 a and first horizontal portion 360 a are engaged such thatfilter cartridge 300 cannot detach from the distribution manifold 332.Venting notches 322 quickly vent any entrained gases allowing the userto continue with the rotatable removal of the filter cartridge 300 suchthat the first angle portion 312 a slides down first angled portion 358a until the filter attachment member 310 a and manifold attachmentmembers 356 a are no longer engaged and filter cartridge 300 can becompletely removed from the distribution manifold 332.

As illustrated in FIG. 39, an adapter 400 can be used to impart featuressuch as, for example, multi-stage engagement mechanisms and controlledenergy venting as previously described in this disclosure, to waterfiltration systems lacking such features. Adapter 400 can, presentlypreferably, comprise a manifold end 402 and a filter end 404. As shownin FIG. 39, adapter 400 is, presently preferably, adapted such that thepreviously described manifold assembly 12 can operatively accept filtercartridge 300. As shown in FIG. 39, manifold end 402 can substantiallyresemble cartridge top member 16 while filter end 404 can substantiallyresemble filter end 334. Manifold end 402 can comprise, for example, apair of manifold attachment members 406 a, 406 b, shown in FIG. 39 ashelical engagement members, such that manifold end 402 is operativelyconnectable to the manifold assembly 12. Filter end 404 can comprises apair of multi-stage engagement mechanism 408, such that filter end 404is operatively connectable to the filter cartridge 300. Manifold end 402can be adapted such that the adapter 400 remains either permanentlyoperatively connected to the manifold assembly 12 or removal of adapter400 from manifold assembly 12 required significantly excess torque ascompared to removal of the filter cartridge 300 from the filter end 404such that adapter 400 need only be attached to manifold assembly 12 onetime.

In addition to rotational engagement of a filter cartridge to amanifold, a filter cartridge 500 and a distribution manifold 502 can belinearly engaged in a multi-stage manner so as allow venting of anyentrained energy within filter cartridge 500, for example, as shown inFIG. 40. Filter cartridge 500 can comprise a filter body 504, a pair ofengagement arms 506 a, 506 b, a filter inlet 508 and a filter outlet510. Engagement arms 506 a, 506 b can comprise an engagement tab 512.Filter inlet 508 and filter outlet 510 can each comprise at least onesealing member 514. Distribution manifold 502 can comprise a manifoldbody 516, a feed supply tube 518, a distribution tube 520, a supply bore522 and a return bore 524. Supply bore 522 and return bore 524 can eachcomprise at least one vent channel 526. Manifold body 516 can comprise afirst engagement recess 528 and a second engagement recess 530 on eachside of the manifold body 516.

Filter cartridge 500 is slidably attached to distribution manifold 502by directing filter inlet 508 into the supply bore 522 and filter outlet510 into the return bore 524. At substantially the same time, engagementarms 506 a, 506 b are, presently preferably, slidably advancing over theoutside of manifold body 516 until engagement tab 512 is retainablypositioned within the corresponding first engagement recess 528. At thispoint, sealing members 514 sealingly engage the inside perimeters of thesupply bore 522 and return bore 524 such that water to be filtered canflow from feed supply tube 518, through supply bore 522, into filtercartridge 500 through the filter inlet 508, out the filter cartridge 500through the filter outlet 510 and to points of use through distributiontube 520.

To remove or replace the filter cartridge 500, one slidably directs thefilter cartridge 500 away from the distribution manifold 502. As theengagement tab 512 approaches the second engagement recess 530, the sealcreated by sealing members 514 and the inner perimeter of supply bore522 and return bore 524 are, presently preferably, broken allowing anyretained energy in the filter cartridge 500 to be released or ventedthrough the vent channel 526. As the filter cartridge 500 is vented,filter cartridge 500 is retainably attached to the distribution manifold502 through the interaction of engagement tabs 512 and the secondengagement recesses 530. In alternative embodiments, the fluidconnections and engagement structures or portions thereof can bereversed relative to the filter cartridge and the manifold assembly toform other slidably engaging filter assemblies. Similarly, other designsof flow connectors can be effectively used for slidably engagingstructures.

While the applicant has disclosed and discussed a variety ofrepresentative embodiments, it will be understood by one of ordinaryskill in the art that a variety of alternative embodiments arecontemplated within the scope and breadth of the present application.Accordingly, the applicant intends to be limited only by the claimsappended hereto.

1. A filter cartridge comprising a filter inlet; a filter media; afilter outlet; a two-stage cartridge engagement mechanism comprising: afully engaged configuration corresponding to full engagement of thefilter cartridge with a compatible manifold assembly; and a partiallyengaged configuration corresponding to partial engagement of the filtercartridge with the compatible manifold assembly; wherein at least one ofthe fully engaged and partially engaged configurations comprises ahorizontal portion; a sealing surface configured to facilitate a firstseal isolating a fluid flow from a non-wetted portion of the compatiblemanifold assembly when the filter cartridge is in the fully engagedconfiguration; and at least one vent port positioned on the filtercartridge and providing a fluid flow passage past the first seal whenthe filter cartridge is in the partially engaged configuration.
 2. Thefilter cartridge of claim 1 wherein the at least one vent port comprisesa notch in the sealing surface.
 3. The filter cartridge of claim 1wherein the at least one vent port comprises a row of ports along anedge of the sealing surface.
 4. The filter cartridge of claim 3 whereineach vent port comprises a notch in the sealing surface.
 5. The filtercartridge of claim 1 wherein the fully engaged configuration of thetwo-stage cartridge engagement mechanism comprises a first horizontalportion and the partially engaged configuration of the two-stagecartridge engagement mechanism comprises a second horizontal portion. 6.The filter cartridge of claim 5 wherein the two-stage cartridgeengagement mechanism further comprises a second angled portionconnecting the first horizontal portion to the second horizontalportion.
 7. The filter cartridge of claim 6 wherein the two-stagecartridge engagement mechanism further comprises a first angled portionadjacent the first horizontal portion.
 8. The filter cartridge of claim7 wherein the two-stage cartridge engagement mechanism further comprisesa third angled portion adjacent the second horizontal portion.
 9. Thefilter cartridge of claim 6 wherein the cartridge engagement mechanismfurther comprises transition between the fully engaged configuration andthe partially engaged configuration, wherein the second angled portionserves to transition the filter cartridge from the fully engagedconfiguration to the partially engaged configuration.
 10. A filtercartridge configured to engage a compatible manifold assembly in a fullyengaged configuration and a partially engaged configuration, the filtercartridge comprising: a projecting insertion wall comprising: anattachment end; a sealing surface depending from an interior perimeterof the attachment end and configured to facilitate a first sealisolating a fluid flow from a non-wetted portion of the compatiblemanifold assembly when the filter cartridge is fully engaged; and amargin surface depending from an exterior perimeter of the attachmentend; a pair of opposed multi-stage filter attachment members disposed onthe margin surface, each multi-stage attachment member comprising: afirst horizontal portion facing away from the attachment end; a secondhorizontal portion facing away from the attachment end; and a secondangled portion connecting the first horizontal portion to the secondhorizontal portion; wherein, in the fully engaged configuration, bothfirst and second horizontal portions seat against the compatiblemanifold assembly and, in the partially engaged configuration, thesecond horizontal portion does not seat against the compatible manifoldassembly; and at least one vent port positioned on the sealing surfaceand providing a fluid flow passage past the first seal when the filtercartridge is in the partially engaged configuration.
 11. The filtercartridge of claim 10 wherein the at least one vent port comprises anotch in the sealing surface.
 12. The filter cartridge of claim 10wherein the at least one vent port comprises a row of ports along anedge of the sealing surface.
 13. The filter cartridge of claim 12wherein each vent port comprises a notch in the sealing surface.
 14. Thefilter cartridge of claim 10 wherein each multi-stage filter attachmentmember further comprises a first angled portion adjacent the firsthorizontal portion.
 15. The filter cartridge of claim 14 wherein eachmulti-stage filter attachment member further comprises a third angledportion adjacent the second horizontal portion.
 16. The filter cartridgeof claim 15 wherein the third angled portion seats against thecompatible manifold assembly when the filter cartridge is fully engagedand does not seat against the compatible manifold assembly when thefilter cartridge is partially engaged.
 17. The filter cartridge of claim14 wherein the first angled portion seats against the compatiblemanifold assembly both when the filter cartridge is fully engaged andwhen the filter cartridge is partially engaged.
 18. The filter cartridgeof claim 10 wherein the second angled portion seats against thecompatible manifold assembly both when the filter cartridge is fullyengaged and when the filter cartridge is partially engaged.
 19. Thefilter cartridge of claim 10 wherein the filter cartridge engages thecompatible manifold assembly in a transition between the fully engagedconfiguration and the partially engaged configuration.
 20. The filtercartridge of claim 19 wherein, in the transition, the second angledportion seats against the compatible manifold assembly, and the firstand second horizontal portions do not seat against the compatiblemanifold assembly.